_ci_ / _build_ : Snap daemon autorun disable

[ianconsolata]

Right now, we automatically start the lotus daemon when someone installs lotus via snapcraft, which in turn automatically starts downloading state snapshots. This changes the workflow so that the lotus daemon snap service is still installed, but is disabled by default in order to allow users who only need a lite node to avoid this resource intensive process.

This should not affect users who already have the snap installed, only users who install the snap fresh.

Checklist

Before you mark the PR ready for review, please make sure that:

• All commits have a clear commit message.
• The PR title is in the form of of <PR type>: <area>: <change being made>
  • example: fix: mempool: Introduce a cache for valid signatures
  • PR type: fix, feat, INTERFACE BREAKING CHANGE, CONSENSUS BREAKING, build, chore, ci, docs,perf, refactor, revert, style, test
  • area: api, chain, state, vm, data transfer, market, mempool, message, block production, multisig, networking, paychan, proving, sealing, wallet, deps
• This PR has tests for new functionality or change in behaviour
• If new user-facing features are introduced, clear usage guidelines and / or documentation updates should be included in https://lotus.filecoin.io or Discussion Tutorials.
• CI is green